Folding type portable radio machine and chassis of the radio machine

ABSTRACT

A folding type portable radio machine, includes a chassis part formed by a first chassis and a second chassis, the second chassis being foldably connected to the first chassis. The chassis part includes a conductive part having conductivity whose full length is an approximately half wave length (λ/2) of a using frequency of the radio machine, and an electric notch.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/664,024, filed Sep. 17, 2003 now U.S. Pat. No. 7,283,853, and nowallowed, which further claims the benefit of priority of Japanese PatentApplication Nos. 2002-274342 filed Sep. 20, 2002 and 2003-092858 filedMar. 28, 2003, the contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to folding type portable radiomachines and chassis of the radio machines, and more particularly, to afolding type portable radio machine, which is folded at the time ofbeing carried and unfolded at the time of being used for telephonecalling or communicating, and a chassis for the phone.

2. Description of the Related Art

A folding type portable radio machine such as a folding type portablephone, including a chassis for the phone, is folded at the time of beingcarried. The radio machine is unfolded at the time of being used fortelephone calling or communicating, and if necessary an antennainstalled inside thereof is extended externally.

FIG. 1 is an exploded perspective view of a related art folding typeportable phone 10. Referring to FIG. 1, the related art folding typeportable phone 10 includes a dial operations key side part 11 held bythe hands of a user, a liquid crystal side part 12 which is folded andunfolded, a left hinge mechanism part 13 a, a right hinge mechanism part13 b, and others.

The left hinge mechanism part 13 a and the right hinge mechanism part 13b are respectively provided at left and right sides of the folding typeportable phone 10 so as to connect the dial operations key side part 11to the liquid crystal side part 12.

The dial operations key side part 11 is formed by combining a plate part20 and a lower part housing 21. A lower part chassis 23 where a printedboard module 22 is provided is installed inside of the dial operationskey side part 11.

The liquid crystal side part 12 is formed by combing a plate part 30 andan upper housing 31. An upper part chassis 34 where a printed boardmodule 32 is provided is installed inside of the liquid crystal sidepart 12.

The left hinge mechanism part 13 a is covered with an arc part 23projecting from an edge of the plate part 20 of the dial operations keyside part 11. The right hinge mechanism part 13 b is covered with an arcpart 33 projecting from an edge of the plate part 30 of the liquidcrystal side part 12.

Furthermore, the printed board module 22 of the dial operations key sidepart 11 and the printed board module 32 of the liquid crystal side part12 are connected by a flexible printed board 40. The flexible printedboard 40 forms a curl configuration at a designated position thereof. Inaddition, an antenna 45 is flexibly received in the lower part housing21 of the dial operation key side part 11. A battery pack 46 is fittedon a lower surface of the lower part housing 21.

Meanwhile, the upper part chassis 34 and the lower part chassis 23 aremolded articles which are made of resin and where metal is vaporized.Furthermore, metal is vaporized on both left hinge mechanism part 13 aand the right hinge mechanism part 13 b so that there is conductivitybetween the dial operation key side part 11 and the liquid crystal sidepart 12. Alternatively, metal is vaporized on neither left hingemechanism part 13 a nor the right hinge mechanism part 13 b so thatthere is no conductivity between the dial operation key side part 11 andthe liquid crystal side part 12.

FIG. 2 is a schematic view of the upper part chassis 34 and the lowerpart chassis 23 in a case where the related art folding type portablephone 10 is folded. More specifically, FIG. 2-(a) is a view seen in theX-Y plane of FIG. 1 and FIG. 2-(b) is a view seen in Y-Z plane of FIG.1.

Referring to FIG. 1 and FIG. 2, when the folding type portable phone iscarried, the upper housing 31 where the upper part chassis 34 isprovided inside is closed against the lower housing 21 where the lowerpart chassis 23 is provided inside. In this case, as shown in FIG. 2,even if the antenna 45 is extended, the upper part chassis 34 is not anobstacle to transmission and receipt of the radio wave by the antenna45.

For example, as shown in Japanese Laid-Open Patent Application No.2002-246821, in a conventional antenna for portable communicationterminals, when a plate antenna is held so as to be separated from ahuman body by 20 mm, the gain of the plate antenna can be made higher by2.5 dB or more over the entire frequency band (1,920-2,170 MHz), thanthe gain of a half-wave length dipole antenna.

Furthermore, as shown in Japanese Laid-Open Patent Application No.2000-216611, there is a conventional folding type mobile phone, whereina monopole antenna is formed by first and second conductive filmsprovided at first and second housings when the phone is unfolded, andthe second conductive film acts like a grounding plane when the phone isfolded.

As shown in Japanese Laid-Open Patent Application No. 11-317610, thereis a conventional antenna of a folding type portable phone thatfunctions as a monopole antenna in a normal operation state and as aslot antenna in a standby state.

Furthermore, as shown in Japanese Laid-Open Patent Application No.2001-77623, there is a small-sized antenna in a stack structure withsufficient passing band width achieved by eliminating mutualinterference by coupling a resonance structure, which has a high centerfrequency ratio on both sides of a coupling layer made of a planarconductive layer, with an external processing unit via a slit formed inthe coupling layer.

However, in a case where the folding type portable phone 10 is unfoldedand the antenna 45 is extended in order to conduct communications andtelephone calling, there might be the following problems with regard totransmission and receipt of the radio wave.

FIG. 3 is a schematic view of the upper part chassis 34 and the lowerpart chassis 23 in a case where the related art folding type portablephone 10 is unfolded. More specifically, FIG. 3-(a) is a view seen inthe X-Y plane of FIG. 1 and FIG. 3-(b) is a view seen in the Y-Z planeof FIG. 1.

Referring to FIG. 1 and FIG. 3, when the communicating or telephonecalling is implemented, the upper housing 31 where the upper partchassis 34 is provided inside thereof is rotated against the lowerhousing 21 where the lower part chassis 23 is provided inside thereof sothat the folding type portable phone 10 is unfolded and the antenna 45is extended.

In this case, as shown in FIG. 3, the upper part chassis 34 is situatedright at the side of the antenna 45. Hence, the upper part chassis 34 isan obstacle for the antenna 45 to transmit and receive the radio wave.

Therefore, the gain of the antenna 45 is degraded so that an radiationefficiency is reduced. Because of this, it may be difficult to implementa high quality telephone call or communications by the related artfolding type portable phone 10.

Furthermore, the conventional portable radio machine such as the foldingtype portable phone 10 shown in FIG. 1 through FIG. 3 generally has anoutside antenna such as a helical antenna or a monopole antenna, or aninstalled antenna such as chip antenna, a plate antenna, or a batchantenna.

In addition, in order to realize the portable radio machine beingapplied to Bluetooth or a radio LAN based on multi-functionalization ofa recent communications developments, it is required for the portableradio machine to have antennas corresponding to respective frequenciesof transmission.

Hence, spaces in which the respective antennas are to be provided isrequired in the portable radio machine. In addition, the foldingportable radio machine is required to be further miniaturized andreduced in weight.

However, it is difficult for the related art portable radio machines toaccomplish both multi-functionalization of the communications andminiaturization and weight savings of the radio machine.

SUMMARY OF THE INVENTION

Accordingly, it is a general object of the present invention to providea novel and useful folding type portable radio machine and a chassis ofthe radio machine in which one or more of the problems described aboveare eliminated.

Another and more specific object of the present invention is to providea folding type portable radio machine having a simple structure whichcan transmit and receive a radio wave efficiently and realize highquality communications, a multifunctional communications and the like,and a chassis of the radio machine.

The above objects of the present invention are achieved by a foldingtype portable radio machine, including:

a chassis part formed by a first chassis and a second chassis, thesecond chassis being foldably connected to the first chassis,

wherein the chassis part includes:

a conductive part having conductivity whose full length is anapproximately half wave length (λ/2) of a using frequency of the radiomachine, and

an electric notch.

The above objects of the present invention are achieved by a foldingtype portable radio machine, including:

a first chassis having conductivity; and

a second chassis having conductivity and being foldably connected to thefirst chassis by a hinge mechanism part,

wherein the hinge mechanism part has a part making the first chassis andthe second chassis have an electric continuity state, and a part notmaking the first chassis and the second chassis have the electriccontinuity state, and

a full length of the first chassis and the second chassis is anapproximately half wave length (λ/2) of a using frequency of the radiomachine.

The above objects of the present invention are achieved by a foldingtype portable radio machine, including:

a first housing having a first chassis having conductivity where aprinted board is provided inside thereof;

a second housing having a second chassis having conductivity whereanother printed board is provided inside thereof;

an antenna being extendable to a back surface of the first housing, theantenna being provided at one of left and right sides of the secondhousing;

wherein the antenna is fed an electric power supply by a feeder circuitof the other printed board provided at the second chassis,

the first chassis and the second chassis are connected by connectionparts provided left and right,

the connection part at the side where the antenna is positionednon-electrically connects the first chassis and the second chassis,

the connection part at the other side electrically connects the firstchassis and the seconds chassis, and

a full length of the radio machine is an approximately half wave length(λ/2) of a using frequency of the radio machine.

The above objects of the present invention are achieved by a foldingtype portable radio machine, including:

a first housing that has a first chassis having conductivity, the firsthousing having a printed board provided inside thereof; and

a second housing that has a second chassis having conductivity, thesecond housing having another printed board provided inside thereof;

wherein the first chassis and the second chassis are physicallyconnected by a first connection part and a second connection partprovided left and right,

the first connection part electrically connects the first chassis andthe second chassis,

the second connection part does not electrically connect the firstchassis and the second chassis,

a full length of the radio machine in a case where the first housing isopened from the second housing is an approximately half wave length(λ₁/2) of a first using frequency of the radio machine;

an interval between the first connection part and the second connectionpart is an approximately one fourth wave length (λ₂/4) of a second usingfrequency of the radio machine; and

the first chassis, the second chassis, the first connection part, andthe second connection part, as an installed antenna of the radiomachine, send and receive radio waves having the first and second usingfrequencies.

The above objects of the present invention are achieved by a chassisprovided inside of a folding type portable radio machine, comprising:

a first chassis part;

a second chassis part; and

a plurality of connection parts provided at the first chassis part andthe second chassis part, the connection parts connecting the firstchassis part and the second chassis part;

wherein only a surface of one of the connection parts at the secondchassis part connecting to the one of the connection parts at the firstchassis part is made of non-conductive material.

Other objects, features, and advantages of the present invention willbecome more apparent from the following detailed description when readin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of the related art folding typeportable phone 10;

FIG. 2 is a schematic view of the upper part chassis 34 and the lowerpart chassis 23 in a case where the related art folding type portablephone 10 is folded;

FIG. 3 is a schematic view of the upper part chassis 34 and the lowerpart chassis 23 in a case where the related art folding type portablephone 10 is unfolded;

FIG. 4 provides three views of a folding type portable phone 100 of afirst embodiment of the present invention in a case where the foldingtype portable phone 100 is unfolded;

FIG. 5 is a view for explaining gamma matching;

FIG. 6 provides graphs indicating a change of input impedance at thegamma matching shown in FIG. 5;

FIG. 7 is a modified schematic view of the gamma matching shown in FIG.5 and is an equivalent view to FIG. 5;

FIG. 8 is a modified schematic view of the gamma matching shown in FIG.7 and is an equivalent view to FIG. 5 and FIG. 7;

FIG. 9 is a graph indicating an impedance characteristic of 900 [MHz]frequency under conditions shown in table 1;

FIG. 10 is a graph indicating an impedance characteristic of 900 [MHz]frequency in a case where L in the table 1 is 0 (zero);

FIG. 11 is a graph indicating an impedance characteristic of 1.5 [GHz]frequency under conditions shown in table 1;

FIG. 12 is an exploded perspective view of the folding type portablephone 100 of the first embodiment of the present invention shown in FIG.4;

FIG. 13 provides schematic views of an upper part chassis 300 and alower part chassis 400 in a case where the folding type portable phone100 shown in FIG. 4 and FIG. 12 is folded;

FIG. 14 is a modified schematic view of FIG. 13 and is an equivalentview to FIG. 13;

FIG. 15 provides schematic views of a folding type portable phone 200 ofa second embodiment of the present invention in a case where the foldingtype portable phone 200 is unfolded;

FIG. 16 is an exploded perspective view of the folding type portablephone 200 shown in FIG. 15;

FIG. 17 provides schematic views for explaining a principle of thefolding type portable phone 200 of a second embodiment of the presentinvention;

FIG. 18 is a schematic view for explaining a relationship between anotch antenna and a resonance frequency;

FIG. 19 is a schematic view electrically equivalent to FIG. 18 in a casewhere Ex mode is applied to a notch antenna 900 shown in FIG. 18;

FIG. 20 provides schematic views showing an electric state in a casewhere a conductor is provided between a left hinge mechanism part 680and a right hinge mechanism part 690 shown in FIG. 17;

FIG. 21 is a schematic view of a state where the folding type portablephone 200 is unfolded;

FIG. 22 is a schematic view of the folding type portable phone 200 in acase where an upper part chassis 500 and a lower part chassis 600 areconnected to each other by a coaxial cable 903;

FIG. 23 is an exploded perspective view of the upper part chassis 500and the lower part chassis 600 of the folding type portable phone 200 ofthe second embodiment of the present invention;

FIG. 24 is a schematic view showing the lower part chassis 600 shown inFIG. 23;

FIG. 25 is an exploded perspective view showing a first structure of aflexible printed board 40 and the vicinity thereof;

FIG. 26 is a perspective view showing a second structure of the flexibleprinted board 40 and the vicinity thereof; and

FIG. 27 is an exploded perspective view of a folding type portable phone950 which is a modified example of the second embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description will now be given, with reference to the FIGS. 4-27, ofembodiments of the present invention. In the following embodiments,folding type portable phones and a chassis of phones are described asexamples of a folding type portable radio machine and a chassis thereof.

First Embodiment

FIG. 4 provides views of a folding type portable phone 100 of a firstembodiment of the present invention in a case where the folding typeportable phone 100 is unfolded. More specifically, FIG. 4-(a) is aperspective view of the folding type portable phone 100, FIG. 4-(b) is aplan view of the folding type portable phone 100, and FIG. 4-(c) is aside view of the folding type portable phone 100.

Referring to FIG. 4, the folding type portable phone 100 of the firstembodiment of the present invention includes an operation key part 101,a liquid crystal display part 102, a connection part 103 for connectingthe operation key part 101 and the liquid crystal display part 102, andothers.

The operation key part 101 is formed by combining an input key board 111and a lower part housing 112. An input key 110 for inputting a phonenumber and others is provided at the input key board 111. A firstprinted board module 117 (See FIG. 12) described below and others areinstalled in the lower part housing 112.

A microphone 114 for gathering voice sounds of the user during telephonecalling is provided at a lower part of the input key board 111.Furthermore, an extensible whip antenna 150 for sending and receiving isprovided at the right side of the inside of the lower part housing 112.

The liquid crystal display part 102 is formed by combining a liquidcrystal display board 153 and an upper housing 154. A liquid crystaldisplay 152 for displaying a picture or a phone number is provided atthe liquid crystal display part 152.

A second printed board module 157 (See FIG. 12) described below andothers are installed in the upper part housing 154. A speaker 155 foroutputting voice sounds of a remote participant of a telephone call isprovided at an upper part of the liquid crystal display board 153.Furthermore, a battery pack 105 is provided at a lower surface of theoperation key part 101 as an electric power supply part.

When the folding type portable mobile phone 100 is carried, namely atthe time of waiting for a telephone call or not communicating, theliquid crystal display part 102 is folded to the operation key part 101.

When communications or telephone calling is initiated, the operation keypart 101 is held by a hand of the user and the liquid crystal displaypart 102 is rotated at the connection part 103 as a center by manualeffort so that the folding type portable mobile phone 100 is unfolded.Furthermore, the antenna 150 is extended from the lower part housing112.

In addition, the full length (the length in a longitudinal direction) ofthe folding type portable phone 100, namely the length “l” shown in FIG.4-(b), is set so as to be an approximately half length of the wavelength (hereinafter “λ”) of a frequency being used.

Meanwhile, gamma matching is used as a matching method for supplyingenergy efficiently from a feeder line to an antenna.

FIG. 5 is a schematic view for explaining the gamma matching. Referringto FIG. 5, the conductive antenna 50 has a full length of approximatelyλ/2. An electric power supply is provided to the antenna 50 by a coaxialcable 51. An external conductor 51 a of the coaxial cable 51 isconnected at a substantially center part of the antenna 50.

Furthermore, an internal conductor 51 b of the coaxial cable 51 isconnected to one end of the first connection part 52 which isconductive, via the condenser (capacitor) C. Another end of the firstconnection part 52 is connected to one end of a second connection part55. Another end of the second connection part 55 is connected to theantenna 50. In FIG. 5, d1 represents the diameter of the antenna 50, d2represents the diameter of the first connection part 52, S representsthe length of the second connection part 55, and L represents the length(distance) from the coaxial cable 51 to the second connection part 55.

FIG. 6 provides graphs indicating a change of input impedance at thegamma matching shown in FIG. 5. Referring to FIG. 6, the vertical axisof the graph represents input impedance and the horizontal axis of thegraph represents a ratio of the length “L” between the coaxial cable 51and the second connection part 55 and λ/4.

A graph in FIG. 6-(a) shows a change of the input impedance in a casewhere the length “S” of the second connection part 55 and the diameterd₂ of the first connection part 52 in FIG. 5 are constant.

Referring to the graph shown in FIG. 6-(a), a curved line (1) shown by asolid line represents an input impedance of a resistance in a case whered₂/d₁ that is a ratio of the diameter d₂ of the first connection part 52to the diameter d₁ of the antenna 50 is large. A curved line (2) shownby a solid line represents an input impedance of a resistance in a casewhere d₂/d₁ is small. A curved line (3) shown by a dotted linerepresents an input impedance of a reactance in a case where d₂/d₁ islarge. A curved line (4) shown by a dotted line represents an inputimpedance of a reactance in a case where d₂/d₁ is small.

A graph in FIG. 6-(b) shows a change of the input impedance in a casewhere the diameter d₁ of the antenna 50, the diameter d₂ of the firstconnection part 52, and d₂/d₁, that is the ratio of the diameter d₂ ofthe first connection part 52 to the diameter d₁ of the antenna 50, areconstant.

Referring to FIG. 6-(b), a curved line (1) shown by a solid linerepresents an input impedance of a resistance in a case where the length“S” of the second connection part 55 is small. A curved line (2) shownby a solid line represents an input impedance of a resistance in a casewhere a length “S” of the second connection part 55 is large. A curvedline (3) shown by a dotted line represents an input impedance of areactance in a case where the length “S” of the second connection part55 is small. A curved line (4) shown by a dotted line represents aninput impedance of a reactance in a case where the length “S” of thesecond connection part 55 is large.

As shown in FIG. 6, the input impedance is changed in a wide range bychanging the capacity (capacitance) of the condenser C (See FIG. 5), thediameter d₁ of the antenna 50 (See FIG. 5), the diameter d₂ of the firstconnection part 52 (See FIG. 5), the length “S” of the second connectionpart 55 (See FIG. 5), and length “L” between the coaxial cable 51 (SeeFIG. 5), and the second connection part 55.

Therefore, it is possible to accomplish impedance matching by selectingproper values of the above mentioned length “L”, the length “S”, and thecapacity of the condenser “C” so as to achieve the same value ofimpedance, 50[Ω], as the coaxial cable 51. Inventors of the presentinvention found that impedance matching of the coaxial cable 51 and theantenna 50 whose full length is approximately λ/2, in a case where thelength “L” is approximately λ/4, the length “S” is a sufficiently shortas compared to λ (for example, approximately λ/10 or less), and thecondenser “C” has a capacity value sufficient to negate (deny) theinductive reactance of the input impedance of the antenna 50.

Meanwhile, FIG. 5, which is a view for explaining the gamma matching,can be redrawn to FIG. 7 and FIG. 8. FIG. 7 is a modified view of thegamma matching shown in FIG. 5 and is an equivalent view to FIG. 5. FIG.8 is a modified view of the gamma matching shown in FIG. 7 and is anequivalent view to FIG. 5 and FIG. 7.

Referring to FIG. 8, the inventors of this application found thatmatching whereby the same impedance as the coaxial cable 51 is achievedis accomplished in a case where the length “S” is sufficiently short ascompared to λ (for example, approximately λ/10 or less), the condenser“C” has a capacity value to deny the inductive reactance of the inputimpedance of the antenna 50, the length “W” is of a length not effectingthe antenna 50 such as λ/4 or less, and the length L is shorter than thelength W.

As shown in FIG. 6, in a case where the length “L” is short, resistanceis small and a radiation of the antenna is degraded. Hence, it isnecessary for the length “L” to be λ/10 or more. The length “L” is notnecessarily a segment line but may be bent at a right angle, forexample.

The inventors of this application found that in cases of 900 [MHz] bandand 1.5 [GHz] band of frequencies, when the length “L”, the length “S”and the capacity of the condenser “C” are set as shown in the followingtable 1, an excellent radiation efficiency [dB] as shown in table 1 canbe achieved.

TABLE 1 FREQUENCY 900 MHz 1.5 GHz Band Band λ/2 [mm] 170 100 L [mm] 3720 W [mm] 47 23.5 S [mm] 10 5 C [pF] 0.5 0.25 Radiation 0.5 −0.3Efficiency [dB]

In a case of 900 [MHz] band of frequencies, when the length “L”, thelength “S” and the capacity of the condenser “C” are set as shown in theabove table 1, an impedance characteristic shown in the graph of FIG. 9is achieved.

Furthermore, in a case of 900 [MHz] band of frequencies when the length“S” and the capacity of the condenser “C” are set as shown in the abovetable 1 and the length “L” is set as 0 (zero), an impedancecharacteristic shown in a graph of FIG. 10 is achieved.

In addition, in a case of 1.5 [GHz] band of frequencies, when the length“L”, the length “S” and the capacity of the condenser “C” are set asshown in the above table 1, an impedance characteristic shown in a graphof FIG. 11 is achieved.

Referring to FIG. 9 through FIG. 11, horizontal axes representfrequencies [MHz] and vertical axes represent return loss [dB], that is,a level loss against input. For example, if the return loss is 0 (zero)[dB], all of the input are reflected.

As shown in the graph of FIG. 9, under conditions shown in table 1, whenthe frequency is between 900 [MHz] and 1000 [MHz], an excellent value of−10 [dB] through −30 [dB] of return loss is obtained so as to obtainimpedance matching.

However, as shown in FIG. 10, when the length “L” is set to 0 (zero),return loss against any frequency is 0 (zero) [dB] so that all of inputare reflected. That is, by setting conditions as shown in table 1, theimpedance matching is obtained as shown in FIG. 9 and FIG. 10.

Furthermore, as shown in the graph in FIG. 11, under the conditionsshown in table 1, when the frequency is approximately 1.5 [GHz], anexcellent value of return loss between −20 [dB] and −30 [dB] is obtainedso that the impedance matching is obtained.

Therefore, as described above, the full length of the folding typeportable phone 100 of the first embodiment of the present inventionshown in FIG. 4, namely the length “l” shown in FIG. 4-(b), is set to alength of an approximately half wave length (λ/2) of a using frequencyand the folding type portable phone 100 has a structure wherein theabove describe gamma matching can be applied, so that it is possible toobtain the impedance matching.

Next, a structure of the folding type portable phone 100 of the presentinvention wherein the above mentioned gamma matching is applied isdescribed. FIG. 12 is an exploded perspective view of the folding typeportable phone 100 of the first embodiment of the present inventionshown in FIG. 4.

Referring to FIG. 12, a second printed board module 157 of a liquidcrystal display part 102 is provided at an upper part chassis 300 whichfunctions as a first chassis part. Furthermore, the upper part chassis300 is provided inside of an upper housing 154, which functions as afirst housing. In addition, a first printed board module 117 of anoperation key part 101 is provided at a lower part chassis 400 whichfunctions as a second chassis part. Furthermore, the lower part chassis400, is provided inside of a lower housing 112, which functions as asecond housing.

The upper part chassis 300 is made of metal such as aluminum, nickel, orthe like, or by vapor-depositing metal material such as aluminum,nickel, magnesium or the like on synthetic resin. The upper part chassis300 and an earth conductor pattern of the second printed board module157 are electrically connected via a spring member or the like.

The upper part chassis 300 is rotatably connected to the lower partchassis 400 via the left hinge mechanism part 180 and the right hingemechanism part 190.

The left hinge mechanism part 180 includes a left hinge 103 a, a leftconnection part 300 a functioning as a first connection part andprovided at a lower part of the upper part chassis 300, and a leftconnection part 400 a functioning as a second connection part andprovided at an upper part of the lower part chassis 400. Similarly, theright hinge mechanism part 190 includes a right hinge 103 b, a rightconnection part 300 b provided at a lower part of the upper part chassis300, and a left connection part 400 b provided at an upper part of thelower part chassis 400.

Both of the left connection parts 300 a and 400 a have hollowconfigurations so that the left hinge 103 a can be inserted. Similarly,both of the right connection parts 300 b and 400 b have hollowconfigurations so that the right hinge 103 b can be inserted.

The lower part chassis 400 is made of metal such as aluminum, nickel, orthe like, or by vapor-depositing metal material such as aluminum,nickel, magnesium or the like on synthetic resin. The right connectionpart 400 b provided at an upper part of the lower part chassis 400 ismade of non-conductive material such as synthetic resin on which metalmaterial is not vapor-deposited. For example, the lower part chassis 400is formed by vapor-depositing the above mentioned metal material on thesynthetic resin in a state where the right connection part 400 b ismasked.

Therefore, when the upper part chassis 300 and the lower part chassis400 are connected by the left hinge mechanism part 180 and the righthinge mechanism part 190, there is continuity between the leftconnection part 300 a and 400 a where the left hinge 103 a is insertedand there is no continuity between the right connection part 300 b and400 b where the right hinge 103 b is inserted.

In order to have more reliable continuity at a side of the left hinge103 a, a connection fitting having a hollow configuration may be putbetween the left connection part 300 a provided at a lower part of theupper part chassis 300 and the left connection part 400 a provided at anupper part of the lower part chassis 400.

Furthermore, in the folding type portable phone 100 shown in FIG. 12,the entire right connection part 400 b is made of non-conductivematerial. However, as long as there is no continuity at the side of theright hinge 103 b, the present invention is not limited to the above.

For example, the above mentioned metal material may be vapor-depositedon the synthetic resin in a state where only a surface 161 is masked soas to make the lower part chassis 400. As a result of this, only thesurface where the right connection part 400 b provided at an upper partof the lower part chassis 400 comes in contact with the right connectionpart 300 b provided at a lower part of the upper part chassis 300, ismade of non-conductive material.

Furthermore, a non-conductive washer member or the like may be putbetween the right connection part 300 b provided at a lower part of theupper part chassis 300 and the right connection part 400 b provided atan upper part of the lower part chassis 400.

In addition, the antenna 150 is provided at a non-conductive side whichis the side of the right connection part 400 b and inside of the lowerpart housing 112 in a state where the antenna 150 can be extended andretracted.

Thus, in the folding type portable phone 100 of the present invention,the upper part chassis 300 of the operation key part 101 is mechanicallyconnected to the lower part chassis 400 of the liquid crystal displaypart 102 via the left hinge mechanism part 180 and the right hingemechanism part 190. However, there is electric continuity only at theleft hinge mechanism 180 between the upper part chassis 300 and thelower part chassis 400. The antenna 150 is positioned on thenon-electric continuity side, namely the side of the right hingemechanism part 190.

The antenna 150 is electrically connected to an electric power supplycircuit of the first printed board module 117 via the designatedelectric power supply surface (a surface positioned at a part indicatedby a dotted line in FIG. 12, for example) of the back surface of thefirst printed board module 117.

Now, a relationship between the above mentioned structure and the abovementioned gamma matching is described.

FIG. 13 is a schematic view of the upper part chassis 300 and the lowerpart chassis 400 in a case where the folding type portable phone 100shown in FIG. 4 and FIG. 12 is unfolded. More particularly, FIG. 13-(a)is a view seen in the X-Y plane of FIG. 4-(a), and FIG. 13-(b) is a viewseen in the Y-Z plane of FIG. 4-(a).

In FIG. 13-(a), the connection part 300 b provided at a lower part ofthe upper part chassis 300 and the right connection part 400 b providedat an upper part of the lower part chassis 400 are indicated by dottedlines just to show that a side of the right hinge mechanism part 190 inFIG. 12 has no electric continuity. Furthermore, arrows in FIG. 13-(b)indicates the electric capacity.

Referring to FIG. 13, the folding type portable phone 100 is unfoldedand the antenna 150 is extended for communicating or telephone calling,so that an electric capacity is formed between the antenna 150 which isconductive and the upper part chassis 300 or the second printed boardmodule 157 which is conductive.

There is no electric continuity at the side of the right hinge mechanismpart 190, namely between the right connection part 300 b provided at alower part of the upper part chassis 300 and the right connection part400 b provided at an upper part of the lower part chassis 400. Hence, anelectric notch, namely an electric cutout is formed between the upperpart chassis 300 and the lower part chassis 400. Accordingly, theelectric state shown in FIG. 13 can be redrawn to FIG. 14.

In FIG. 14, a condenser “C” represents an electric capacity formedbetween the antenna 150 which is conductive and the upper part chassis300 which is conductive. A part indicated by diagonal lines representsthe above mentioned electric notch.

The electric state of the folding type portable phone 100 shown in FIG.14 is equivalent to the gamma matching circuit shown in FIG. 8. As shownin FIG. 4-(b), a full length “l” of the folding type portable phone 100is suitable for a length of approximately λ/2 of the using frequency.The impedance matching can be achieved at a using frequency band byadjusting the capacity of the condenser C shown in FIG. 14, the length Lbetween a right end part 170 of the upper part chassis 300 and the lefthinge mechanism part 180, and the length S of the left connection part300 a provided at the lower part of the upper pact chassis 300 and theleft connection part 400 a provided at the upper part of the lower pactchassis 400, which are connected by the left hinge 103 a.

The inventors of this application paid attention to electric continuityand non-electric continuity of the side of the left hinge mechanism part180 (the left connection part 300 a provided at the lower part of theupper pact chassis 300 and the left connection part 400 a provided atthe upper part of the lower pact chassis 400) and the side of the righthinge mechanism part 190 (the right connection part 300 b provided atthe lower part of the upper pact chassis 300 and the right connectionpart 400 b provided at the upper part of the lower pact chassis 400),and measured radiation efficiency of the antenna 150. A table 2 showsthe results of the measurements. In the table 2, a value of theradiation efficiency [dB] shows a characteristic in a case where a λ/2dipole antenna is 0 (zero) [dB].

TABLE 2 RADIATION EFFICINCY [dB] MEASUREMENT CONDITION A SIDE OF A SIDEOF LEFT RIGHT MECHANISM MECHANISM FREAQUENCY 180 190 819 [MHz] 949 [MHz]CONTINUITY CONTINUITY −8.5 −7.0 NON- NON- −6.6 −7.9 CONTINUITYCONTINUITY CONTINUITY NON- −0.0 −1.3 CONTINUITY

As shown in table 2, in a case where the right connection part 400 b wasformed without vapor-depositing a metal material so that there was noelectric continuity between the right connection part 300 b and theright connection part 400 b but there was an electric continuity betweenthe left connection part 300 a and the left connection part 400 a, −0.0[dB] of the radiation efficiency for a frequency in a state of 819 [MHz]and −1.3 [dB] of the radiation efficiency for a frequency of 949 [MHz]were obtained. Therefore, under the above mentioned conditions, betterradiation efficiency can be obtained than in a case where both sides ofthe left hinge mechanism part 180 and the right hinge mechanism part 190have electric continuity or both sides do not have electric continuity.

That is, under the above mentioned structure of the folding typeportable phone 100, the antenna 150 provided in the lower part housing112, the lower part chassis 400, the left hinge mechanism part 180 (theleft connection part 300 a, the left connection part 400 a, and the lefthinge 103 a), and the upper part chassis 300 that functions as anobstacle of the antenna conventionally, function in a body, as a λ/2antenna having good radiation efficiency.

Furthermore, in the above mentioned embodiment, the lower part chassis400 can be formed without vapor-depositing metal material on the rightconnection part 400 b. Hence, it is possible to manufacture the abovementioned lower part chassis 400 easily.

In a case where the folding type portable phone 100 is folded, since theupper part chassis 300 is not positioned where it works as an obstacleto the antenna 150, good radiation characteristics can be obtained.

Thus, according to the folding type portable phone 100 of the firstembodiment of the present invention, in a case where the folding typeportable phone is unfolded and the antenna is extended so as to conductphone calling and communications, it is possible to transmit and receivea radio wave efficiently and realize high quality phone calling andcommunicating.

Although there is no electric continuity between the right connectionpart 300 b and the right connection part 400 b in the above mentionedembodiment, the present invention is not limited to the above. That is,it is possible to manufacture a the folding type portable phone whichfunctions as a λ/2 dipole antenna that can obtain effective high gain ata using frequency band, wherein by adjusting the capacity of thecondenser “C”, the length “L”, and the length “S” for gamma matching asshown in FIG. 8, impedance matching can be achieved.

For example, in the above mentioned example, the full length of thefolding type portable phone 100, namely the length “l” shown in FIG.4-(b) is set so as to have a length of approximately λ/2 of the usingfrequency. However, the sum of the full length of the second printedboard module 157 and the full length of the first printed board module117 may be suitable for approximately λ/2 of the using frequency.

Second Embodiment

Next, a second embodiment of the present invention will be explained. Indrawings for the second embodiment of the present invention, parts thatare the same as the parts shown in drawings for the first embodiment aregiven the same reference numerals, and explanation thereof will beomitted.

FIG. 15 provides views of a folding type portable phone 200 of a secondembodiment of the present invention in a case where the folding typeportable phone 200 is unfolded. More particularly, FIG. 15-(a) is aperspective view of the folding type portable phone 200, FIG. 15-(b) isa plan view of the folding type portable phone 200, and FIG. 15-(c) is aside view of the folding type portable phone 200. FIG. 16 is an explodedperspective view of the folding type portable phone 200 shown in FIG.15.

Referring to FIG. 15, the folding type portable phone 200 of the secondembodiment of the present invention, as well as the folding typeportable phone 100 of the first embodiment of the present invention,includes an operation key part 101, a liquid crystal display part 102, aconnection part 103 for connecting the operation key part 101 and theliquid crystal display part 102, and others.

Referring to FIG. 16, the operation key part 101 is formed by combiningan input key board 111 and a lower part housing 112 functioning as asecond housing. A lower part chassis 600 functioning as a second chassisis provided inside of the lower part housing 112. A first printed boardmodule 117 is provided at the lower part chassis 600.

The liquid crystal display part 102 is formed by combining the liquidcrystal display board 153 and the upper part housing 154 functioning asa first housing. An upper part chassis 500 functioning as a firstchassis is provided inside of the upper part housing 154. The liquidcrystal display 152 and the second printed board module 157 are providedat the upper part chassis 500.

The upper part chassis 500 and the lower part chassis 600 include theleft hinge mechanism part 680 and the right hinge mechanism part 690.

The left hinge mechanism part 680 is covered with an arc part 23projecting from an edge of the input key board part 111 of the dialoperations key side part 101. The right hinge mechanism part 690 iscovered with an arc part 33 projecting from an edge of the liquidcrystal display board 153 of the liquid crystal side part 102. The lefthinge mechanism part 680 and the right hinge mechanism part 690 form theconnection part 103 shown in FIG. 15. Details of structures of the lefthinge mechanism part 680 and the right hinge mechanism part 690 will bedescribed below.

Furthermore, the first printed board module 117 of the dial operationskey side part 101 and the second printed board module 157 of the liquidcrystal side part 102 are connected by a flexible printed board 40. Theflexible printed board 40 is put between the left hinge mechanism part680 and the right hinge mechanism part 690 and is connected to the firstprinted board module 117 and the second printed board module 157 viaconnectors. The flexible printed board 40 is bendable and flexible so asto form a curl configuration at a designated position thereof.

In addition, an external antenna 250 for sending and receiving isinstalled at the right side of the inside of the lower part housing 112.The external antenna 250 is fixed there without being flexible, unlikethe whip antenna 150 of the folding type portable phone 100 of the firstembodiment of the present invention.

Referring back to FIG. 15, when the folding type portable mobile phone200 is carried, namely at the time of waiting for a telephone calling ornot communicating, the liquid crystal display part 102 is folded to theoperation key part 101. When the communicating or telephone calling isinitiated, the operation key part 101 is held by a hand of the user andthe liquid crystal display part 102 is rotated at the connection part103 as a center by manual effort so that the folding type portablemobile phone 200 is unfolded.

The full length of the folding type portable phone 200 (the length inthe longitudinal direction of the folding type portable phone 200),namely a length “l” shown in FIG. 15-(b), is set so as to be suitablefor approximately half of the wave length λ₁ of the first usingfrequency.

According to the first embodiment of the present invention as shown inFIG. 4, FIG. 13 and others, the full length of the folding type portablephone 100 is approximately half of the wave length of the usingfrequency, there is electric continuity at the left hinge mechanism part180, and the antenna 150 is positioned at a side of the right hingemechanism part 190 where there is no electric continuity, so thatimpedance matching can be obtained by using the above mentioned gammamatching.

In the second embodiment of the present invention, the impedancematching at the first using frequency is achieved by using the abovementioned gamma matching, and the impedance matching at the second usingfrequency is achieved by using the relationship between the notchantenna and resonance frequency. First principles of the secondembodiment are next described and then detailed structures thereof aredescribed.

FIG. 17 is a view for explaining a principle of the folding typeportable phone 200 of the second embodiment of the present invention.More particularly, FIG. 17-(a) is a view seen in the X-Y plane of FIG.15-(a) and shows a state of the upper part chassis 500 and the lowerpart chassis 500 shown in FIG. 16 when the folding type portable phone200 is unfolded. In FIG. 17-(a), a part 680 indicated by solid linesrepresents a part where there is an electric continuity, and a part 690indicated by dotted lines represents a part mechanically connected butwhere there is no electric continuity. FIG. 17-(b) is a viewelectrically equivalent to the view of FIG. 17-(a).

In the folding type portable phone 200 of the second embodiment of thepresent invention, a length “l” shown in FIG. 15-(b) is set so as to besuitable for half of the wave length λ₁ of the first using frequency. Asshown in FIG. 17-(a), although there is no electric continuity at theright hinge mechanism part 690, there is electric continuity at partsincluding the left hinge mechanism part 680 other than the right hingemechanism part 690.

Therefore, an electric notch namely electric cutout is formed betweenthe upper part chassis 500 and the lower part chassis 600 as shown bydiagonal lines in FIG. 17-(b). An electric state shown in FIG. 17-(b) isequivalent to a state shown in FIG. 8 that is a modification of thegamma matching shown in FIG. 5 and FIG. 7.

The impedance matching can be achieved at the first using frequency bythe above mentioned gamma matching, in a state where a full length “l”of the folding type portable phone 200 is suitable for a length of anapproximately one half of the wavelength (λ/2) of the first usingfrequency, the capacity of the condenser C is adjusted based on changeof multiplier by a known method, the length L in the X1-X2 direction ofthe electric notch is adjusted, and the length S in the Y1-Y2 directionof the electric notch is adjusted. Here, the length L is a length in theX1-X2 direction is a length in X1-X2 direction between ends of the upperpart chassis 500 and the lower part chassis 600 at a side where theelectric notch is formed and the left hinge mechanism part 680 that haselectric continuity.

Because of the above mentioned adjustment, the upper part chassis 500,the lower part chassis 600, and the left hinge mechanism part 680function in a body, as an antenna having a length of approximately halfof a wave length λ₁ of the first using frequency and a good electriccontinuity.

Meanwhile, the inventors of this application paid attention to arelationship between the so-called notch antenna, having an electricnotch shown by diagonal lines in FIG. 17, and a resonance frequency sothat impedance matching at the second using frequency can be obtainedaccording to the second embodiment.

FIG. 18 is a view for explaining a relationship between a notch antennaand a resonance frequency. FIG. 19 is a view electrically equivalent toFIG. 18 in a case where Ex mode is applied to a notch antenna 900 shownin FIG. 18. In FIG. 18, the electric notch is indicated by diagonallines as well as FIG. 17-(b).

Referring to FIG. 18, in a notch antenna 900 having an electric notchinside thereof, “S” represents a length in an x direction of theelectric notch, “L” represents a length in a y direction of the electricnotch, and “λ₂” represents a wavelength at a frequency when the notchantenna is used. Under the above mentioned circumstances, resonanceoccurs in two state, namely “Ex mode” wherein “L” is longer than “S” andL equals λ₂/4 and “Ey mode” wherein “S” is longer than “L” and S equalsλ₂/4.

However, in a case of the Ey mode, it is necessary to provide a longcoaxial cable for feeding electric power to the notch antenna. Hence, itmay not be desirable to apply the Ey mode to a folding type portablephone.

Because of this, the inventors of this application decided to apply theEx mode to the folding type portable phone so that the length of thecoaxial cable 901 can be minimized. In a case where the Ex mode isapplied to the folding type portable phone, the notch antenna 900 shownin FIG. 18 is electrically equivalent to the monopole antenna shown inFIG. 19 and having a full length of λ₂/4.

Thus, it is possible to obtain impedance matching at the second usingfrequency by setting “L” that is a length in the y direction of theelectric notch shown in FIG. 18 as a length suitable for λ₂/4 of thesecond using frequency and adjusting the capacity of the condenser “C”shown in FIG. 17-(b).

Meanwhile, when waiting for telephone calling and the folding typeportable phone is being carried, the phone is folded. Therefore, even ina state where the folding type portable phone is folded, it is necessaryfor the folding type portable phone to have a structure whereinresonance occurs at the first and second using frequencies.

More particularly, even in the state where the folding type portablephone is folded, the folding type portable phone should have a structurewherein the above mentioned electric notch is formed. Therefore, theinventors of this application realized that a conductor needs to beprovided between the left hinge mechanism part 680 and the right hingemechanism part 690 shown in FIG. 17. An electrically equivalent state tothe above mentioned state is shown in FIG. 20. Here, the electric notchis shown by diagonal lines in FIG. 20. More particularly, FIG. 20-(a)shows a case where the folding type portable phone is unfolded and FIG.20-(b) shows a case where the folding type portable phone is folded.

Referring to FIG. 20, a conductive member 902 is provided in an X1direction from the left hinge mechanism part 680, namely at a side ofthe right hinge mechanism part 690. Furthermore, although the feedingpoint of an electric power supply is provided at the upper part chassis500 in the example shown in FIG. 18, here the feeding point of anelectric power supply is provided at the conductive member 902.Therefore, as shown by diagonal lines in FIG. 20, the electric notchhaving a width “S′” in the Y1-Y2 direction is formed between theconductive member 902 and the lower part chassis 600.

Opening and closing of the upper part chassis 500 and the lower partchassis 600 are achieved by the left hinge mechanism part 680 and theright hinge mechanism part 690 as a center of opening and closing.Because of this structure, as shown in FIG. 20-(b), even if the upperpart chassis 500 is closed against the lower part chassis 600, theelectric notch is formed between the conductive member 902 and the lowerpart chassis 600.

Thus, regardless of folding or unfolding of the folding type portablephone 200, the electric notch can be formed, and thereby it is possibleto achieve resonance at a designated second using frequency.

Furthermore, as shown in FIG. 15, the full length of the folding typeportable phone 200 is set as being suitable for approximately half ofthe wave length λ₁ of the first using frequency. When the folding typeportable phone 200 is folded, the full length of the folding typeportable phone 200 is approximately one fourth of the wave length λ₁ ofthe first using frequency, as shown in FIG. 21.

More particularly, FIG. 21-(a) shows a state where the folding typeportable phone 200 is unfolded and FIG. 21-(b) shows a state where thefolding type portable phone 200 is folded. In FIG. 21, an arrowrepresents the direction of electric current for the folding typeportable phone 200.

Furthermore, the drawing to the left of FIG. 21-(a) indicates anelectric current distribution in a state where the folding type portablephone 200 is unfolded. The vertical axis represents a position in a fulllength direction of the folding type portable phone 200. The horizontalaxis represents the amount of electric current. The upper half of theelectric current distribution indicates electricity distribution at theupper part chassis 500 and the lower half of the electric currentdistribution indicates electricity distribution at the lower partchassis 600.

As shown in FIG. 21, under the structure shown in FIG. 17, when thefolding type portable phone 200 is folded, the direction of the electriccurrent at the upper part chassis 500 is reverse to the direction of theelectric current at the lower part chassis 600 so that the electriccurrents at the upper part and lower part chassis 500 and 600contradicts each other. That may cause the collapse of a resonant stateat the first using frequency.

Accordingly, as shown in FIG. 22, the upper part chassis 500 and thelower part chassis 600 are connected by a coaxial cable 903 having afull length suitable for approximately half of the wave length λ₁ of thefirst using frequency.

FIG. 22-(a) shows a state where the folding type portable phone 200 isunfolded and FIG. 22-(b) shows a state where the folding type portablephone 200 is folded. In FIG. 22, an arrow represents the direction ofelectric current in the folding type portable phone 200.

Furthermore, the drawing to the left of FIG. 22 indicates an electriccurrent distribution in a state where the folding type portable phone200 is unfolded. The vertical axis represents a position in a fulllength direction of the folding type portable phone 200. The horizontalaxis represents the amount of electric current. A part indicated by anarrow “A” of the electricity distribution is suitable for the coaxialcable 903.

As shown in FIG. 22, since the upper part chassis 500 and the lower partchassis 600 are connected by a coaxial cable 903 having a full lengthsuitable for approximately half of the wave length λ₁ of the first usingfrequency, even if the folding type portable phone 200 is folded, thedirection of the electric current at the upper part chassis 500 is sameas the direction of the electric current at the lower part chassis 600.

That is, by connecting the upper part chassis 500 and the lower partchassis 600 with the coaxial cable 903, even if the folding typeportable phone 200 is folded, the gamma matching of the folding typeportable phone, whose full length is suitable for approximately half ofthe wave length λ₁ of the first using frequency, can be used, as well asin the state where the folding type portable phone 200 is unfolded.

Therefore, even if the folding type portable phone 200 is folded, it ispossible to prevent contradiction of the directions of the electriccurrents at the upper and lower parts chassis 500 and 600 shown in FIG.21 so that it is possible for resonance to occur at the first usingfrequency. As described above, since resonance of the second usingfrequency is caused by the length “L” in the y direction of the electricnotch in FIG. 17, it is possible to obtain resonance of the second usingfrequency regardless of states of folding and unfolding of the foldingtype portable phone 200.

Next, a detailed structure of the folding type portable phone 200 of thesecond embodiment of the present invention is described. In the foldingtype portable phone 200, based on the above mentioned principle, it ispossible to obtain impedance matching at the first using frequency byusing gamma matching, and obtain impedance matching at the second usingfrequency by using the relationship between the notch antenna and theresonant frequency.

FIG. 23 is an exploded perspective view of the upper part chassis 500and the lower part chassis 600 of the folding type portable phone 200 ofthe second embodiment of the present invention.

Referring to FIG. 23, the liquid crystal display 152 and the secondprinted board module 157 are provided at the upper part chassis 500shown in FIG. 16. The first printed board module 117 is provided at thelower part chassis 600.

The upper part chassis 500 is made of metal such as aluminum, nickel, orthe like, or by vapor-depositing metal material such as aluminum,nickel, magnesium or the like on synthetic resin. The upper part chassis500 and an earth conductive pattern of the second printed board module157 are electrically connected to each other via a spring member or thelike.

The upper part chassis 500 is rotatably connected to the lower partchassis 600 via the left hinge mechanism part 680 and the right hingemechanism part 690.

The left hinge mechanism part 680 includes a left hinge 103 a, a leftconnection part 300 a functioning as a first connection part andprovided at a lower part of the upper part chassis 500, and a leftconnection part 400 a functioning as a second connection part andprovided at an upper part of the lower part chassis 600. Similarly, theright hinge mechanism part 690 includes a right hinge 103 b, a rightconnection part 300 b provided at a lower part of the upper part chassis500, and a right connection part 400 b provided at an upper part of thelower part chassis 600.

The left connection parts 300 a and 400 a have hollow configurations sothat the left hinge 103 a can be inserted. Similarly, the rightconnection parts 300 b and 400 b have hollow configurations so that theright hinge 103 b can be inserted.

The lower part chassis 600 is made of metal such as aluminum, nickel, orthe like, or by vapor-depositing metal material such as aluminum,nickel, magnesium or the like on synthetic resin. The right connectionpart 400 b provided at an upper part of the lower part chassis 400 ismade of non-conductive material such as synthetic resin on which metalmaterial is not vapor-deposited. For example, the lower part chassis 600is formed by vapor-depositing the above mentioned metal material on thesynthetic resin in a state where the right connection part 400 b ismasked. Therefore, it is possible to easily form the lower part chassis600 having the above mentioned right connection part 400 b.

The upper part chassis 500 and the lower part chassis 600 are connectedto each other by the left hinge mechanism part 680 and the right hingemechanism part 690. There is electric continuity between the leftconnection parts 300 a and 400 a where the left hinge 103 a is inserted.There is no electric continuity between the right connection parts 300 band 400 b where the right hinge 103 a is inserted.

In order to have more reliable continuity at a side of the left hingemechanism part 680, a connection fitting 160 having a hollowconfiguration may be put between the left connection part 300 a providedat a lower part of the upper part chassis 500 and the left connectionpart 400 a provided at an upper part of the lower part chassis 600.

Under the above structure, the upper part chassis 500 and the lower partchassis 600 are physically connected to each other by the left hingemechanism part 680 functioning as a first connection part and the righthinge mechanism part 690 functioning as a second connection part. But,there is electric continuity at only the left hinge mechanism part 680between the upper part chassis 500 and the lower part chassis 600.Therefore, the electric notch described with reference to FIG. 17through FIG. 19 is formed between the left hinge mechanism part 680 andthe right hinge mechanism part 690. Hence, a notch antenna is formed bythe upper part chassis 500, the lower part chassis 600, and the lefthinge mechanism part 680.

More particularly, a length in the Z1-Z2 direction in FIG. 23 betweenthe left hinge mechanism part 680 which provides electric continuitybetween the upper part chassis 500 and the lower part chassis 600 andthe right hinge mechanism part 690 which does not provide electriccontinuity between the upper part chassis 500 and the lower part chassis600, is set to be suitable for a length “L” described with reference toFIG. 17 through FIG. 19, namely approximately one fourth of the wavelength λ₂ of the second using frequency.

Furthermore, as described above, the full length of the folding typeportable phone 200 (a length in a vertical direction of the folding typeportable phone 200), namely the length “l” shown in FIG. 15-(b), is setto be suitable for approximately half of the wave length λ₁ of the firstusing frequency.

Therefore, in a state where the folding type portable phone 200 isunfolded, the impedance matching at the first using frequency can beachieved with gamma matching by properly adjusting the capacity of thecondenser provided inside of the folding type portable phone 200. Andalso, the impedance matching at the second using frequency can beachieved by using the relationship between the notch antenna and theresonant frequency.

In the above embodiment, the entire right connection part 400 b providedat an upper part of the lower part chassis 600 is formed by anon-conductive material. However, the present invention is not limitedto the above as long as the side of the right hinge mechanism part 690does not provide electric continuity.

For example, the lower part chassis 600 may be formed byvapor-depositing the above mentioned metal material on the syntheticresin in a state where the surface 161 where the right connection part400 b provided at the upper part of the lower part chassis 600 comes incontact with the right connection part 300 b provided at the lower partof the upper part chassis 500 is masked, so that only the surface 161may be formed by non-conductive material.

Furthermore, a non-conductive washer member or the like may be putbetween the right connection part 300 b provided at the lower part ofthe upper part chassis 500 and the right connection part 400 b providedat the upper part of the lower part chassis 600.

Furthermore, in the above mentioned embodiment, the full length of thefolding type portable phone 200, namely the length “l” shown in FIG.15-(b) is set to be suitable for approximately half of the wave lengthλ₁ of the first using frequency. However, the present invention is notlimited to the above. For example, a sum of the full length of thesecond printed board module 157 and the full length of the first printedboard module 117 may be suitable for approximately λ₁/2 of the firstusing frequency.

Meanwhile, FIG. 24 is a view showing the lower part chassis 600 shown inFIG. 23. More particularly, FIG. 24-(a) is a plan view thereof and FIG.24-(b) is a side view thereof in Z2-Z1 direction.

As shown in FIG. 23 and FIG. 24, at the left connection part 400 aprovided at an upper part of the lower part chassis 600, a conductivemember 902 is extended from a part positioned lower than a hollow partof the left connection part 400 a in the Z1 direction, namely to a sideof the right hinge mechanism part 690, so as to form a length “S′”between the lower part chassis 600 and the conductive member 902 and notto reach the right connection part 400 b.

Opening and closing of the upper part chassis 500 and the lower partchassis 600 are conducted in a state where the left hinge mechanism part680 and the right hinge mechanism part 690 are centers of the operationsof opening and closing. Because of the conductive material 902, evenwhen the upper part chassis 500 is closed against the lower part chassis600, an electric notch is formed so as to have a length “S′” between theconductive member 902 and the lower part chassis 600.

That is, regardless of folding and unfolding states of the folding typeportable phone 200, the electric notch can be formed so that resonanceat the second using frequency can be achieved.

Meanwhile, as described above with reference to FIG. 15, the firstprinted board module 117 provided at the upper chassis 500 and thesecond printed board module 157 provided at the lower part chassis 600are electrically connected by a flexible printed board 40. The flexibleprinted board 40 is bendable and flexible so as to form a curlconfiguration at a designated position thereof.

FIG. 25 is a perspective view showing a first structure of a flexibleprinted board 40 and the vicinity thereof. FIG. 26 is a perspective viewshowing a second structure of the flexible printed board 40 and thevicinity thereof.

Referring to FIG. 25, a connector 910 for connecting to the firstprinted board module 117 provided at the upper chassis 500 is providedat one end of the flexible printed board 40 shown by a one point dottedline. In addition, a connector 911 for connecting to the second printedboard module 157 provided at the lower chassis 600 is provided at theother end of the flexible printed board 40. When the flexible printedboard 40 is connected to the printed board modules 117 and 157 via theconnectors 910 and 911, a curl part 41 is formed so as to form at leastone spiral.

An axial member 912 is inserted in an axial direction inside of the curlpart 41 formed at the flexible printed board 40 so that the curl part 41is prevented from being deformed due to long term repeated operations offolding and unfolding the folding type portable phone 200. Furthermore,a protection sheet 913 is provided along an external circumference ofthe curl part 41 and thereby the flexible printed board 40 is protected.

A plurality of hole forming parts 914 are formed at the protection sheet913. A coaxial cable 903 passes through the hole forming parts 914 so asto wind almost around the external circumference of the first printedboard module 117 along the protection sheet 913. The coaxial cable 903is a coaxial line which connects the first printed board module 117 andthe second printed board module 157 and has a length suitable for beingapproximately half of the wave length λ₁ of the first using frequency.

Alternatively, instead of the protection sheet 913 having the abovementioned the hole forming parts 914, as shown in FIG. 26, a holeforming part 915 in an axial direction may be provided at the center ofthe axial member 912 so that the above mentioned coaxial cable 903 maypass through the hole forming part 915.

Thus, the first printed board module 117 provided at the lower chassis600 and the second printed board module 157 provided at the upper partchassis 500 are connected by the coaxial cable 903 having a lengthsuitable for approximately half of the wave length λ₁ of the first usingfrequency in a state where the curl part 41 formed at the flexibleprinted board 40 is used. Therefore, even if the folding type portablephone 200 is folded so that the upper chassis 500 is closed against thelower part chassis 600, it is possible to apply gamma matching of afolding type portable phone having a full length of approximately λ₁/2so that resonance can be achieved at the first using frequency, as wellas a state where the folding type portable phone 200 is unfolded.

Thus, the conductive member 902 is extended from the left connectionpart 400 a to the side of the right hinge mechanism part 690 that doesnot provide electric continuity, so as to form a gap having the length“S′” between the lower part chassis 600 and the conductive member 902.Furthermore, the first printed board module 117 provided at the lowerpart chassis 600 and the second printed board module 157 provided at theupper part chassis 500 are connected by the coaxial cable 903 having alength suitable for approximately half of the wave length λ₁ of thefirst using frequency. Hence, even in a state where the folding typeportable phone 200 is folded, resonance at the first and second usingfrequencies can be achieved.

Thus, according to the folding type portable phone 200 of the secondembodiment of the present invention, the upper part chassis 500, thelower part chassis 600, and the hinge mechanism parts 680 and 690function in a body as an internal antenna at different using frequencybands (dual bands), more particularly as a modified gamma matching typehalf wavelength dipole antenna having an effective high gain.Accordingly, it is possible to transmit and receive radio wavesefficiently at the dual bands so that high quality telephone calling andcommunicating can be implemented.

Furthermore, resonance can be achieved at respective frequencies byusing the internal antenna using the electric notch formed by the upperpart chassis 500, the lower part chassis 600, and the hinge mechanismparts 680 and 690 provided inside of the folding type portable phone200, without providing the external antenna corresponding to therespective frequencies for receiving and sending (for example, a whipantenna) at a space inside of the folding type portable phone 200.Hence, it is possible to minimize the size of the folding type portablephone and make it light weight.

For example, the above mentioned folding type portable phone may bemodified to a folding type portable phone 950 shown in FIG. 27. Here,FIG. 27 is an exploded perspective view of a folding type portable phone950 which is a modified example of the second embodiment of the presentinvention.

Referring to FIG. 27, the folding type portable phone 950 has asubstantially same structure as the above mentioned folding typeportable phone 200 except not having the external antenna 150 shown inFIG. 16. As described above, according to the second embodiment of thepresent invention, since it corresponds to use for the dual bands byonly the internal antenna formed in a body by the upper part chassis500, the lower part chassis 600, and the hinge mechanism parts 680 and690, an external antenna itself such as a whip antenna is not provided.

According to the structure shown in FIG. 27, a part of the externalantenna, extending to the outside of the folding type portable phone950, is not provided. Hence, it is possible to avoid encountering of anobstacle when the folding type portable phone 950 is taken into/out of apocket, bag, or the like so that smooth taking in and out can beachieved. Furthermore, it is possible to minimize the size of thefolding type portable phone 950 and making the weight thereof light canbe achieved. In addition, it is possible to use a space conventionallyallocated to the external antenna for other purposes.

Meanwhile, in the respective examples shown in FIG. 15 through FIG. 27,the second embodiment of the present invention is described by using thefolding type portable phone. However, the principle (See FIG. 17 throughFIG. 19) used in the second embodiment of the present invention can beused for a so-called straight type portable phone, which is used withoutbeing folded even at the time of being carried (at the time of waitingfor phone calling and at the time of non-communication).

That is, a configuration of a board provided inside of the straight typeportable phone is formed as having a plan view of rectangular shape withone side having a part being cut out so that an electric notch isprovided in the vicinity of the center of the board. In addition, thelong side of the board is set to be suitable for approximately half ofthe wave length λ₁ of the first using frequency and the long side of theelectric notch is set to be suitable for approximately half of the wavelength λ₂ of the second using frequency.

Under the above mentioned structure, the straight type portable phone iselectrically equivalent to a state where the folding type portable phone200 shown in FIG. 17-(a) is unfolded. Hence, based on the principle ofthe second embodiment of the present invention described with referenceto FIG. 17 through FIG. 19, it is possible to achieve resonance atdifferent using frequency bands so that high quality telephone callingand communicating can be implemented as a modified gamma matching typehalf wavelength dipole antenna having an effective high gain.

The present invention is not limited to these embodiments, butvariations and modifications may be made without departing from thescope of the present invention.

For example, although the folding type portable phone and the chassisthereof are described in the above mentioned embodiments, the presentinvention is not limited to the above. The present invention may beapplied to other kinds of folding type portable radio machines, whichare folded at the time of being carried (waiting for being called andcommunicating, non-communication) and unfolded at the time of being usedfor telephone calling or communicating, and the chassis of the radiomachines.

This patent application is based on Japanese Priority Patent ApplicationNo. 2002-274342 filed on Sep. 20, 2002, and Japanese Priority PatentApplication No. 2003-92858 filed on Mar. 28, 2003, the entire contentsof which are hereby incorporated by reference.

What is claimed is:
 1. A chassis provided inside a folding type portableradio machine, comprising: a first chassis part having a first part of afirst connection part and a first part of a second connection part; asecond chassis part having a second part of the first connection partand a second part of the second connection part; and an antenna providedin the second chassis part on a side in the vicinity of the secondconnection part, the antenna being extendable in a direction toward thefirst chassis part, wherein the first part of the first connection partcorresponds to and contacts the second part of the first connectionpart, the first part of the second connection part corresponds to andcontacts the second part of the second connection part, and the firstconnection part and the second connection part respectively connect thefirst chassis part and the second chassis part, wherein a contactsurface of the second part of the second connection part of the secondchassis part contacts the first part of the second connection part ofthe first chassis part and is made of non-conductive material, andwherein a contact surface of the second part of the first connectionpart of the second chassis part contacts the first part of the firstconnection part of the first chassis part and is made of a conductivematerial, such that an electric notch is formed between the firstchassis part and the second chassis part in a region corresponding tothe second connection part.
 2. The folding type portable radio machineas claimed in claim 1, wherein the first connection part and the secondconnection part are formed of a rigid material and are fixedly connectedto the first and second chassis parts, respectively, and are rotatablyconnected to each other.
 3. The folding type portable radio machine asclaimed in claim 1, wherein the first connection part and the secondconnection part define an axis of rotation between the first and secondchassis parts, about which the first and second chassis parts arerotatably connected to each other.